In order to equalize the flow profile in flat spray nozzles, it is known for a pre-nozzle having a central circular opening to be arranged before the nozzle orifice which is provided with a long nozzle opening.
In a known construction this pre-nozzle is inserted loosely between the nozzle orifice and the nozzle carrier and is held in position by the connecting nut which connects the nozzle orifice to the housing support. The disadvantage of this known construction is the poor centering of the pre-nozzle, as a consequence of which the nozzle openings of the pre-nozzle and the nozzle orifice are not exactly aligned with one another.
In a further known construction the pre-nozzle is pressed into the nozzle orifice. This fixed connection does ensure satisfactory centering, but it excludes the possibility of simple cleaning of the nozzle orifice.